On pp. 84-85 of Ancient Aliens on the Moon, the perennially error-prone Mike Bara displays one of the favorite images of all "lunar anomalists" — a 1965 image returned by the Soviet Moon-Mars probe Zond 3.
He writes this about it, as usual ignoring all reasonable explanations for the feature and emphasizing the one that supports his very shaky thesis:
"Located on the lunar horizon ... a large, eroded dome-like structure was plainly visible in the lower right corner ... [T]his "Zond 3 dome" extended several miles above the airless lunar horizon. ... I suspect that what Zond 3 captured was in fact the battered remains of a watch crystal type of dome just beneath the larger protecting scaffolding we've seen other places on the lunar surface."
Well, as I said, this one has done the rounds of the conspiracy nutcases for many years, and I got involved in a bit of argy-bargy this week with a poster to the Fuckery-Bookery page The Final Frontier. The guy slapped up the picture and captioned it "A dome on the moon." I challenged him to report the coordinates of the feature, so that I could examine the much better images in the LROC library to see if there was anything real at that point. He didn't know the coordinates. He didn't know the resolution of the image. He didn't know what image processing was used by Zond.
I had my own guess as to the coordinates, based on the relationship to Mare Orientale, which is clearly seen in the whole Zond image (and I thank Carol Behan for pointing that out.) I guessed it would have to be somewhere within this frame, centered on 24.5 S, 59 W. Here's a permalink.
The original poster responded "Well obviously you will not find any evidence on anything that has been publicly released," which I thought probably signaled that we were at the end of any meaningful discussion.
Don Davis to the rescue
The renowned space artist Don Davis monitors that FB page, and his attempts to knock some sense into the flim-flam men and Branch Hoaglandians have been heroic and tireless. Don's information about the Moon and Mars is highly reliable and very detailed. I reproduce his contribution here with Don's permission and with only very slight editing.
"Here is the story behind that Zond Moon photo, as a background to others interested in this subject.
The history of early Lunar exploration is chronicled in the NASA Special Publication 'Exploring Space With A Camera'.
The far side of the Moon was first revealed by a pair of Soviet Lunar probes, beginning with Luna 3 in early October 1959 which sent back static degraded transmissions of its view of the Moon revealing a rarity of the dark 'maria' across much of the side we never see from Earth, but little else.
On July 20, 1965 the next Soviet Lunar probe, Zond 3, obtained a view of the Eastern regions of the Lunar Far side, also including features visible from Earth for reference. It used an improved film camera which developed the film on board and scanned the negative, transmitting the image to Earth. The early Zond 3 photo releases were as prints, of which the frame shown in the NASA SP referenced above is an example. Soviet news release photos were not often known for their quality control, so making claims based on some minor detail in them is risky. There may also have been an effort to degrade the quality a little in the copying process to hide some of what they were capable of doing, as similar film readout methods were being used in spy satellites planned and flown by both nations. Such was the Cold War context of early space exploration.
I look at the bright blotch over the sky in the lower right corner and wonder what caused it, and where in the 1960s Soviet era duplication chain it appeared.
There are two possibilities. Either a real visual display of large size was captured by the original camera optics along the Lunar horizon, or the light splotch was a photographic imperfection in the original or a fault in the duplication chain as a shiny original caught an uneven reflection of a ceiling light or something like that.
Fortunately the original Zond photography of the Moon has been recovered from the transmission data as the developed film was scanned on the spacecraft. Here is the image, Zond 3 picture 28.
There is no sign of any bright projection from the Lunar limb (edge). Nor does it appear in any of the other Moon images made by Zond 3.
This demonstrates that the original camera images show no extraordinary display corresponding to what appears in the initial very contrasty press release print.
But let us play 'What if?. What if the camera really saw something recorded as such a blotch projecting beyond the limb of the Moon? [T]his could resemble a volcanic plume such as [can be] seen erupting from Jupiters moon Io.
So where on the Moon would such an erupting volcano (or ancient alien dome, if one wanted to commit oneself rather precariously) have to be located? 60 Degrees W, 30 Degrees South is about where that spot on the edge of the Moon should be just by comparing the photo with a front side Moon map. [NOTE: This point falls within the rectangular area I had guessed at]
If one was really careful about this a roughly rectangular area on the map could be defined as where something that large could be, if it is continuously there. it's 'base' would appear to be nearly as wide as the dark lava pool filled crater named Grimaldi, the prominent dark oval near the right limb. It would be about 60 miles across, just shy of 100 kilometers. This region of the Moon can be readily inspected through a telescope, and the lack of anything bright looming over that region of the Moon is the best evidence one can have that the most likely origin for that bright spot on the print was a mundane one somewhere in the photolabs of the Soviet news services.
Of course, anyone wanting to make a claim of something extraordinary on the Moon is obliged to include as evidence the latest photos of the region taken by the Lunar Recon Orbiter. Orbiters from Japan, China and India have also mapped virtually the entire Moon independently, but the US satellite has the best quality data. Go explore the super detailed photo maps now becoming available, imagine being there one day on a rover or on foot!"